An end carboxyl bearing reactive vinyl monomer exemplified by acrylic acid, methacrylic acid and the like has been well known as a constituting unit of an acrylic resin.
Such monomer is usually copolymerized with other acrylic monomers as acrylates, methacrylates and the like, to improve the adhesion properties of the resulted resin to a metal substrate or improve the curing properties of the resin to be compounded with an aminoplast resin.
However, in the heretofore proposed end carboxyl bearing vinyl monomers, the chain length between the vinyl group and the carboxyl group is relatively short and therefore, even when incorporated into a vinyl resin, the curing acceleration effect is not so good and the adhesion improvement is rather poor. Thus, the actual use of these monomers has been limited in certain cases.
It is, therefore, an object of the invention to provide a novel class of end carboxyl bearing reactive vinyl monomers, which may produce, when incorporated into a vinyl resin, a strong catalytic action in a crosslinking reaction of the resulted resin with an aminoplast resin, developing desired properties to the formed coating.
An additional object of the invention is to provide a class of end carboxyl bearing reactive vinyl monomers which are useful in the preparation of vinyl resins having various desirable properties.
A further object of the invention is to provide a process for preparing such novel monomers. Additional objects of the invention shall be clear from the following descriptions of the specification and the claims.